runsvd: shrink by Vladimir
[oweals/busybox.git] / networking / telnet.c
index caca89d2d00ce271d7ff33835b4b0b2240d8fdad..5d7ecef3bf40f3b563caccf32bc2367d64e16ba9 100644 (file)
@@ -52,15 +52,14 @@ enum {
 
 typedef unsigned char byte;
 
+enum { netfd = 3 };
 
 struct globals {
-       int     netfd; /* console fd:s are 0 and 1 (and 2) */
-       short   iaclen; /* could even use byte */
+       int     iaclen; /* could even use byte, but it's a loss on x86 */
        byte    telstate; /* telnet negotiation state from network input */
        byte    telwish;  /* DO, DONT, WILL, WONT */
        byte    charmode;
        byte    telflags;
-       byte    gotsig;
        byte    do_termios;
 #if ENABLE_FEATURE_TELNET_TTYPE
        char    *ttype;
@@ -69,7 +68,7 @@ struct globals {
        const char *autologin;
 #endif
 #if ENABLE_FEATURE_AUTOWIDTH
-       int     win_width, win_height;
+       unsigned win_width, win_height;
 #endif
        /* same buffer used both for network and console read/write */
        char    buf[DATABUFSIZE];
@@ -78,9 +77,13 @@ struct globals {
        struct termios termios_def;
        struct termios termios_raw;
 };
-
 #define G (*(struct globals*)&bb_common_bufsiz1)
-
+void BUG_telnet_globals_too_big(void);
+#define INIT_G() do { \
+       if (sizeof(G) > COMMON_BUFSIZE) \
+               BUG_telnet_globals_too_big(); \
+       /* memset(&G, 0, sizeof G); - already is */ \
+} while (0)
 
 /* Function prototypes */
 static void rawmode(void);
@@ -92,12 +95,13 @@ static int subneg(byte c);
 
 static void iacflush(void)
 {
-       write(G.netfd, G.iacbuf, G.iaclen);
+       write(netfd, G.iacbuf, G.iaclen);
        G.iaclen = 0;
 }
 
 #define write_str(fd, str) write(fd, str, sizeof(str) - 1)
 
+static void doexit(int ev) NORETURN;
 static void doexit(int ev)
 {
        cookmode();
@@ -108,7 +112,7 @@ static void conescape(void)
 {
        char b;
 
-       if (G.gotsig)   /* came from line  mode... go raw */
+       if (bb_got_signal)      /* came from line  mode... go raw */
                rawmode();
 
        write_str(1, "\r\nConsole escape. Commands are:\r\n\n"
@@ -117,18 +121,18 @@ static void conescape(void)
                        " z     suspend telnet\r\n"
                        " e     exit telnet\r\n");
 
-       if (read(0, &b, 1) <= 0)
-               doexit(1);
+       if (read(STDIN_FILENO, &b, 1) <= 0)
+               doexit(EXIT_FAILURE);
 
        switch (b) {
        case 'l':
-               if (!G.gotsig) {
+               if (!bb_got_signal) {
                        do_linemode();
                        goto rrturn;
                }
                break;
        case 'c':
-               if (G.gotsig) {
+               if (bb_got_signal) {
                        will_charmode();
                        goto rrturn;
                }
@@ -139,46 +143,44 @@ static void conescape(void)
                rawmode();
                break;
        case 'e':
-               doexit(0);
+               doexit(EXIT_SUCCESS);
        }
 
        write_str(1, "continuing...\r\n");
 
-       if (G.gotsig)
+       if (bb_got_signal)
                cookmode();
 
  rrturn:
-       G.gotsig = 0;
+       bb_got_signal = 0;
 
 }
 
 static void handlenetoutput(int len)
 {
-       /*      here we could do smart tricks how to handle 0xFF:s in output
-        *      stream  like writing twice every sequence of FF:s (thus doing
-        *      many write()s. But I think interactive telnet application does
-        *      not need to be 100% 8-bit clean, so changing every 0xff:s to
-        *      0x7f:s
+       /* here we could do smart tricks how to handle 0xFF:s in output
+        * stream like writing twice every sequence of FF:s (thus doing
+        * many write()s. But I think interactive telnet application does
+        * not need to be 100% 8-bit clean, so changing every 0xff:s to
+        * 0x7f:s
         *
-        *      2002-mar-21, Przemyslaw Czerpak (druzus@polbox.com)
-        *      I don't agree.
-        *      first - I cannot use programs like sz/rz
-        *      second - the 0x0D is sent as one character and if the next
-        *               char is 0x0A then it's eaten by a server side.
-        *      third - whay doy you have to make 'many write()s'?
-        *              I don't understand.
-        *      So I implemented it. It's realy useful for me. I hope that
-        *      others people will find it interesting to.
+        * 2002-mar-21, Przemyslaw Czerpak (druzus@polbox.com)
+        * I don't agree.
+        * first - I cannot use programs like sz/rz
+        * second - the 0x0D is sent as one character and if the next
+        *      char is 0x0A then it's eaten by a server side.
+        * third - whay doy you have to make 'many write()s'?
+        *      I don't understand.
+        * So I implemented it. It's realy useful for me. I hope that
+        * others people will find it interesting too.
         */
 
        int i, j;
        byte * p = (byte*)G.buf;
        byte outbuf[4*DATABUFSIZE];
 
-       for (i = len, j = 0; i > 0; i--, p++)
-       {
-               if (*p == 0x1d)
-               {
+       for (i = len, j = 0; i > 0; i--, p++) {
+               if (*p == 0x1d) {
                        conescape();
                        return;
                }
@@ -189,7 +191,7 @@ static void handlenetoutput(int len)
                        outbuf[j++] = 0x00;
        }
        if (j > 0)
-               write(G.netfd, outbuf, j);
+               write(netfd, outbuf, j);
 }
 
 static void handlenetinput(int len)
@@ -197,73 +199,64 @@ static void handlenetinput(int len)
        int i;
        int cstart = 0;
 
-       for (i = 0; i < len; i++)
-       {
+       for (i = 0; i < len; i++) {
                byte c = G.buf[i];
 
-               if (G.telstate == 0) /* most of the time state == 0 */
-               {
-                       if (c == IAC)
-                       {
+               if (G.telstate == 0) { /* most of the time state == 0 */
+                       if (c == IAC) {
                                cstart = i;
                                G.telstate = TS_IAC;
                        }
-               }
-               else
-                       switch (G.telstate)
-                        {
-                        case TS_0:
-                                if (c == IAC)
-                                        G.telstate = TS_IAC;
-                                else
-                                        G.buf[cstart++] = c;
-                                break;
-
-                        case TS_IAC:
-                                if (c == IAC) /* IAC IAC -> 0xFF */
-                                {
-                                        G.buf[cstart++] = c;
-                                        G.telstate = TS_0;
-                                        break;
-                                }
-                                /* else */
-                                switch (c)
-                                {
-                                case SB:
-                                        G.telstate = TS_SUB1;
-                                        break;
-                                case DO:
-                                case DONT:
-                                case WILL:
-                                case WONT:
-                                        G.telwish =  c;
-                                        G.telstate = TS_OPT;
-                                        break;
-                                default:
-                                        G.telstate = TS_0;     /* DATA MARK must be added later */
-                                }
-                                break;
-                        case TS_OPT: /* WILL, WONT, DO, DONT */
-                                telopt(c);
-                                G.telstate = TS_0;
-                                break;
-                        case TS_SUB1: /* Subnegotiation */
-                        case TS_SUB2: /* Subnegotiation */
-                                if (subneg(c))
-                                        G.telstate = TS_0;
-                                break;
-                        }
+               } else
+                       switch (G.telstate) {
+                       case TS_0:
+                               if (c == IAC)
+                                       G.telstate = TS_IAC;
+                               else
+                                       G.buf[cstart++] = c;
+                               break;
+
+                       case TS_IAC:
+                               if (c == IAC) { /* IAC IAC -> 0xFF */
+                                       G.buf[cstart++] = c;
+                                       G.telstate = TS_0;
+                                       break;
+                               }
+                               /* else */
+                               switch (c) {
+                               case SB:
+                                       G.telstate = TS_SUB1;
+                                       break;
+                               case DO:
+                               case DONT:
+                               case WILL:
+                               case WONT:
+                                       G.telwish =  c;
+                                       G.telstate = TS_OPT;
+                                       break;
+                               default:
+                                       G.telstate = TS_0;      /* DATA MARK must be added later */
+                               }
+                               break;
+                       case TS_OPT: /* WILL, WONT, DO, DONT */
+                               telopt(c);
+                               G.telstate = TS_0;
+                               break;
+                       case TS_SUB1: /* Subnegotiation */
+                       case TS_SUB2: /* Subnegotiation */
+                               if (subneg(c))
+                                       G.telstate = TS_0;
+                               break;
+                       }
        }
-       if (G.telstate)
-       {
-               if (G.iaclen)                   iacflush();
+       if (G.telstate) {
+               if (G.iaclen) iacflush();
                if (G.telstate == TS_0) G.telstate = 0;
-
                len = cstart;
        }
 
        if (len)
-               write(1, G.buf, len);
+               write(STDOUT_FILENO, G.buf, len);
 }
 
 static void putiac(int c)
@@ -350,7 +343,7 @@ static void putiac_naws(byte c, int x, int y)
 }
 #endif
 
-static char const escapecharis[] = "\r\nEscape character is ";
+static char const escapecharis[] ALIGN1 = "\r\nEscape character is ";
 
 static void setConMode(void)
 {
@@ -437,7 +430,8 @@ static void to_sga(void)
        } else if (G.telwish == WONT)
                return;
 
-       if ((G.telflags ^= UF_SGA) & UF_SGA) /* toggle */
+       G.telflags ^= UF_SGA; /* toggle */
+       if (G.telflags & UF_SGA)
                putiac2(DO, TELOPT_SGA);
        else
                putiac2(DONT, TELOPT_SGA);
@@ -529,12 +523,6 @@ static int subneg(byte c)
        return FALSE;
 }
 
-static void fgotsig(int sig)
-{
-       G.gotsig = sig;
-}
-
-
 static void rawmode(void)
 {
        if (G.do_termios)
@@ -547,10 +535,11 @@ static void cookmode(void)
                tcsetattr(0, TCSADRAIN, &G.termios_def);
 }
 
-void BUG_telnet_globals_too_big(void);
+/* poll gives smaller (-70 bytes) code */
+#define USE_POLL 1
 
-int telnet_main(int argc, char** argv);
-int telnet_main(int argc, char** argv)
+int telnet_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int telnet_main(int argc UNUSED_PARAM, char **argv)
 {
        char *host;
        int port;
@@ -562,9 +551,7 @@ int telnet_main(int argc, char** argv)
        int maxfd;
 #endif
 
-       if (sizeof(G) > sizeof(bb_common_bufsiz1))
-               BUG_telnet_globals_too_big();
-       /* memset(&G, 0, sizeof G); - already is */
+       INIT_G();
 
 #if ENABLE_FEATURE_AUTOWIDTH
        get_terminal_width_height(0, &G.win_width, &G.win_height);
@@ -580,11 +567,8 @@ int telnet_main(int argc, char** argv)
                cfmakeraw(&G.termios_raw);
        }
 
-       if (argc < 2)
-               bb_show_usage();
-
 #if ENABLE_FEATURE_TELNET_AUTOLOGIN
-       if (1 & getopt32(argc, argv, "al:", &G.autologin))
+       if (1 & getopt32(argv, "al:", &G.autologin))
                G.autologin = getenv("USER");
        argv += optind;
 #else
@@ -597,20 +581,20 @@ int telnet_main(int argc, char** argv)
        if (*argv) /* extra params?? */
                bb_show_usage();
 
-       G.netfd = create_and_connect_stream_or_die(host, port);
+       xmove_fd(create_and_connect_stream_or_die(host, port), netfd);
 
-       setsockopt(G.netfd, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
+       setsockopt(netfd, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
 
-       signal(SIGINT, fgotsig);
+       signal(SIGINT, record_signo);
 
 #ifdef USE_POLL
-       ufds[0].fd = 0; ufds[1].fd = G.netfd;
+       ufds[0].fd = 0; ufds[1].fd = netfd;
        ufds[0].events = ufds[1].events = POLLIN;
 #else
        FD_ZERO(&readfds);
-       FD_SET(0, &readfds);
-       FD_SET(G.netfd, &readfds);
-       maxfd = G.netfd + 1;
+       FD_SET(STDIN_FILENO, &readfds);
+       FD_SET(netfd, &readfds);
+       maxfd = netfd + 1;
 #endif
 
        while (1) {
@@ -626,7 +610,7 @@ int telnet_main(int argc, char** argv)
                        /* timeout */
                case -1:
                        /* error, ignore and/or log something, bay go to loop */
-                       if (G.gotsig)
+                       if (bb_got_signal)
                                conescape();
                        else
                                sleep(1);
@@ -636,12 +620,12 @@ int telnet_main(int argc, char** argv)
 #ifdef USE_POLL
                        if (ufds[0].revents) /* well, should check POLLIN, but ... */
 #else
-                       if (FD_ISSET(0, &rfds))
+                       if (FD_ISSET(STDIN_FILENO, &rfds))
 #endif
                        {
-                               len = read(0, G.buf, DATABUFSIZE);
+                               len = read(STDIN_FILENO, G.buf, DATABUFSIZE);
                                if (len <= 0)
-                                       doexit(0);
+                                       doexit(EXIT_SUCCESS);
                                TRACE(0, ("Read con: %d\n", len));
                                handlenetoutput(len);
                        }
@@ -649,17 +633,17 @@ int telnet_main(int argc, char** argv)
 #ifdef USE_POLL
                        if (ufds[1].revents) /* well, should check POLLIN, but ... */
 #else
-                       if (FD_ISSET(G.netfd, &rfds))
+                       if (FD_ISSET(netfd, &rfds))
 #endif
                        {
-                               len = read(G.netfd, G.buf, DATABUFSIZE);
+                               len = read(netfd, G.buf, DATABUFSIZE);
                                if (len <= 0) {
                                        write_str(1, "Connection closed by foreign host\r\n");
-                                       doexit(1);
+                                       doexit(EXIT_FAILURE);
                                }
-                               TRACE(0, ("Read netfd (%d): %d\n", G.netfd, len));
+                               TRACE(0, ("Read netfd (%d): %d\n", netfd, len));
                                handlenetinput(len);
                        }
                }
-       }
+       } /* while (1) */
 }